[llvm] [Target] Remove `Target::resetTargetOptions` (PR #201825)

[Matt Arsenault via llvm-commits]

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@@ -121,7 +121,7 @@ class LLVM_ABI TargetMachine {
   std::optional<PGOOptions> PGOOption;
 
 public:
-  mutable TargetOptions Options;
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arsenm wrote:

Can this be const now 

https://github.com/llvm/llvm-project/pull/201825